fix(nixpacks): make setup cmd a single-line TOML string to avoid parse error; keep same apt packages

Author: z.murodov

nixpacks.toml

@@ -2,20 +2,7 @@
 # Ensure Python is present for Nixpacks Python phase, plus native deps for OpenCV/MediaPipe
 nixPkgs = ['python311', 'libGL', 'libglvnd', 'pkg-config', 'glib', 'zlib', 'mesa', 'xorg.libX11', 'xorg.libXext', 'xorg.libXrender']
 cmds = [
-  'apt-get update -y && DEBIAN_FRONTEND=noninteractive apt-get install -y \\
-    libgl1 \\
-    libglvnd0 \\
-    libglx-mesa0 \\
-    libgl1-mesa-dri \\
-    libglib2.0-0 \\
-    libxext6 \\
-    libxrender1 \\
-    libxfixes3 \\
-    libsm6 \\
-    libxcb1 \\
-    libxau6 \\
-    libxdmcp6 \\
-    libglx0'
+  'apt-get update -y && DEBIAN_FRONTEND=noninteractive apt-get install -y libgl1 libglvnd0 libglx-mesa0 libgl1-mesa-dri libglib2.0-0 libxext6 libxrender1 libxfixes3 libsm6 libxcb1 libxau6 libxdmcp6 libglx0'
 ]
 
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